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        <h1 id="Cloud-Computing-Chapter3"   >
          <a href="#Cloud-Computing-Chapter3" class="heading-link"><i class="fas fa-link"></i></a><a href="#Cloud-Computing-Chapter3" class="headerlink" title="Cloud Computing Chapter3"></a>Cloud Computing Chapter3</h1>
      <p>Understanding Cloud Computing(理解云计算)</p>
<span id="more"></span>


        <h2 id="origins-and-Influences（起源和影响）"   >
          <a href="#origins-and-Influences（起源和影响）" class="heading-link"><i class="fas fa-link"></i></a><a href="#origins-and-Influences（起源和影响）" class="headerlink" title="origins and Influences（起源和影响）"></a>origins and Influences（起源和影响）</h2>
      <p>–A Brief History   </p>
<blockquote>
<p>1961,computer scientist John McCarthy publicly proposed<code> utility computing</code>（效用计算）<br>1969 ARPANET project  “spread of computer utilities”<br>Mid-1990s  google, email,facebook,<br>Late 1990s  salesforce.com remotely provisioned service<br>2002 Amazon web services platform<br>2006 - the term <code>cloud computing</code>(云计算 )emerged in the commercial arena.<br>Amazon launched its Elastic Compute Cloud（弹性云计算） (EC2) services that enabled organizations to “lease” (租赁)computing capacity and processing power to run their enterprise applications.<br> Google Apps also began providing <code>browser-based</code> enterprise applications in the same year, and three years later, the <code>Google App Engine</code> became another historic milestone.   </p>
</blockquote>

        <h3 id="Definitions"   >
          <a href="#Definitions" class="heading-link"><i class="fas fa-link"></i></a><a href="#Definitions" class="headerlink" title="Definitions"></a>Definitions</h3>
      <p>– Gartner(1):  </p>
<blockquote>
<p>a style of computing in which <code>scalable and elastic</code> IT-enabled capabilities are  delivered <code>as a service </code>to external customers using Internet technologies. </p>
</blockquote>
<p>–Forrester(2) :     </p>
<blockquote>
<p>a standardized IT capability (services, software, or infrastructure) delivered via Internet technologies in a <code>pay-per-use, self-service</code> way.  </p>
</blockquote>
<p>–NIST (3):   </p>
<blockquote>
<p>Cloud computing is a model for enabling <code>ubiquitous, convenient, on-demand </code>network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction.   </p>
</blockquote>
<p>–This book (4):   </p>
<blockquote>
<p>Cloud computing is a specialized form of <code>distributed computing</code> that introduces <code>utilization models</code> for<code> remotely</code> provisioning <code>scalable and   measured</code> resources.   </p>
</blockquote>

        <h3 id="Business-Drivers-商业驱动力"   >
          <a href="#Business-Drivers-商业驱动力" class="heading-link"><i class="fas fa-link"></i></a><a href="#Business-Drivers-商业驱动力" class="headerlink" title="Business Drivers 商业驱动力"></a>Business Drivers 商业驱动力</h3>
      <p>–Capacity Planning 容量规划：<br>     • the process of determining and fulfilling future demands of an organization’s IT resources, products, and services.<br>• capacity planning strategies: </p>
<blockquote>
<p>1.Lead Strategy – adding capacity to an IT resource in anticipation of demand<br>2.Lag Strategy – adding capacity when the IT resource reaches its full capacity<br>3.Match Strategy – adding IT resource capacity in small increments, as demand   increases   </p>
</blockquote>
<p>–Cost Reduction   降低成本<br>–Organizational Agility  组织灵活性  </p>

        <h3 id="Technology-Innovations-技术创新"   >
          <a href="#Technology-Innovations-技术创新" class="heading-link"><i class="fas fa-link"></i></a><a href="#Technology-Innovations-技术创新" class="headerlink" title="Technology Innovations 技术创新"></a>Technology Innovations 技术创新</h3>
      <p>–Clustering 集群化  </p>
<blockquote>
<p>a group of independent IT resources that are interconnected and work as a single system. System failure rates are reduced while availability and reliability are increased, since redundancy and failover features are inherent to the cluster. </p>
</blockquote>
<p>–Grid Computing 网格计算  </p>
<blockquote>
<p>provides a platform in which computing resources are organized into one or more logical pools.  </p>
</blockquote>
<p>–Virtualization 虚拟化   </p>
<blockquote>
<p>a technology platform used for the creation of virtual instances of IT resources.  </p>
</blockquote>
<p>-Technology Innovations vs. Enabling Technologies<br>    计算创新和使能技术   </p>

        <h2 id="Basic-Concepts-and-Terminology"   >
          <a href="#Basic-Concepts-and-Terminology" class="heading-link"><i class="fas fa-link"></i></a><a href="#Basic-Concepts-and-Terminology" class="headerlink" title="Basic Concepts and Terminology"></a>Basic Concepts and Terminology</h2>
      
        <h3 id="Cloud"   >
          <a href="#Cloud" class="heading-link"><i class="fas fa-link"></i></a><a href="#Cloud" class="headerlink" title="Cloud"></a>Cloud</h3>
      <p>–A cloud refers to a distinct IT environment that is designed for the purpose of remotely provisioning scalable and measured IT resources.<br>–Symbol  </p>
<center>
    <img 
    src="https://pic.imgdb.cn/item/622df6f35baa1a80ab5b938d.jpg">
</center>


        <h3 id="IT-Resource"   >
          <a href="#IT-Resource" class="heading-link"><i class="fas fa-link"></i></a><a href="#IT-Resource" class="headerlink" title="IT Resource"></a>IT Resource</h3>
      <p>–An IT resource is a physical or virtual IT-related artifact that can be either software-based, such as a virtual server or a custom software program, or hardware-based, such as a physical server or a network device .</p>
<center>
    <img 
    src="https://pic.imgdb.cn/item/622df7995baa1a80ab5bbb9f.jpg">
</center>
      

<center>
    <img 
    src="https://pic.imgdb.cn/item/622df7bf5baa1a80ab5bc573.jpg">
</center>


        <h3 id="On-Premise-企业内部的"   >
          <a href="#On-Premise-企业内部的" class="heading-link"><i class="fas fa-link"></i></a><a href="#On-Premise-企业内部的" class="headerlink" title="On-Premise  企业内部的"></a>On-Premise  企业内部的</h3>
      <p>———<code>An IT resource that is on-premise cannot be cloud-based  </code><br>—An on-premise IT resource can access and interact with a cloud-based IT resource.<br> –An on-premise IT resource can be moved to a cloud, thereby changing it to a cloud-based IT resource.<br> –Redundant deployments of an IT resource can exist in both on-premise and cloud-based environments  </p>

        <h3 id="Cloud-Consumers-and-Cloud-Providers"   >
          <a href="#Cloud-Consumers-and-Cloud-Providers" class="heading-link"><i class="fas fa-link"></i></a><a href="#Cloud-Consumers-and-Cloud-Providers" class="headerlink" title="Cloud Consumers and Cloud Providers"></a>Cloud Consumers and Cloud Providers</h3>
      <p>–cloud provider 云提供者</p>
<blockquote>
<p>The party that provides cloud-based IT resources </p>
</blockquote>
<p>–cloud consumer 云用户</p>
<blockquote>
<p>The party that uses cloud-based IT resources</p>
</blockquote>

        <h3 id="Scaling-可扩展性"   >
          <a href="#Scaling-可扩展性" class="heading-link"><i class="fas fa-link"></i></a><a href="#Scaling-可扩展性" class="headerlink" title="Scaling 可扩展性"></a>Scaling 可扩展性</h3>
      <p>–Horizontal Scaling 水平扩展<br>–Vertical Scaling  垂直扩展  </p>
<p>–Horizontal Scaling</p>
<blockquote>
<p>－scaling out 向外扩展<br>    －scaling  in  向内扩展</p>
</blockquote>
<center>
    <img 
    src="https://pic.imgdb.cn/item/622ec4c45baa1a80aba5caed.jpg">
</center>
--Vertical Scaling

<blockquote>
<p>－scaling up  向上扩展<br> －scaling  down  向下扩展</p>
</blockquote>
<center>
    <img  
    src="https://pic.imgdb.cn/item/622ecfd95baa1a80abaac72b.jpg">

</center>


        <h3 id="Cloud-Service-云服务"   >
          <a href="#Cloud-Service-云服务" class="heading-link"><i class="fas fa-link"></i></a><a href="#Cloud-Service-云服务" class="headerlink" title="Cloud Service 云服务"></a>Cloud Service 云服务</h3>
      <p>–<code>A cloud service</code> is any IT resource that is made remotely accessible via a cloud.  </p>
<center>
    <img 
    src="https://pic.imgdb.cn/item/622ed0265baa1a80abaadf13.jpg">

</center>

<p>The driving <code>motivation</code> behind cloud computing is to provide IT resources as services that <code>encapsulate other</code> IT resources<br>–<code>remotely</code>.<br>–<code>as-a-service</code><br>–<code>a service-level agreement (SLA)</code></p>

        <h3 id="Cloud-Service-Consumer-云服务用户"   >
          <a href="#Cloud-Service-Consumer-云服务用户" class="heading-link"><i class="fas fa-link"></i></a><a href="#Cloud-Service-Consumer-云服务用户" class="headerlink" title="Cloud Service Consumer  云服务用户"></a>Cloud Service Consumer  云服务用户</h3>
      <p>–a <code>temporary</code> runtime role assumed by a software program when it <code>accesses</code> a cloud service  </p>
<center>
    <img
    src="https://pic.imgdb.cn/item/622ed0bb5baa1a80abab0536.jpg">  
</center>
 

        <h2 id="Goals-and-Benefits-目标和收益"   >
          <a href="#Goals-and-Benefits-目标和收益" class="heading-link"><i class="fas fa-link"></i></a><a href="#Goals-and-Benefits-目标和收益" class="headerlink" title="Goals and Benefits  目标和收益"></a>Goals and Benefits  目标和收益</h2>
      
        <h3 id="Reduced-Investments-and-Proportional-Costs-降低的投资与成比例的开销"   >
          <a href="#Reduced-Investments-and-Proportional-Costs-降低的投资与成比例的开销" class="heading-link"><i class="fas fa-link"></i></a><a href="#Reduced-Investments-and-Proportional-Costs-降低的投资与成比例的开销" class="headerlink" title="Reduced Investments and Proportional Costs(降低的投资与成比例的开销)"></a>Reduced Investments and Proportional Costs(降低的投资与成比例的开销)</h3>
      <p>–Common measurable benefits to cloud consumers include:</p>
<blockquote>
</blockquote>
<p> On-demand access to pay-as-you-go computing resources<br>The perception of having unlimited computing resources<br>The ability to add or remove IT resources at a fine-grained level<br> Abstraction of the infrastructure   </p>

        <h3 id="Increased-Scalability-提高的可扩展性"   >
          <a href="#Increased-Scalability-提高的可扩展性" class="heading-link"><i class="fas fa-link"></i></a><a href="#Increased-Scalability-提高的可扩展性" class="headerlink" title="Increased Scalability (提高的可扩展性)"></a>Increased Scalability (提高的可扩展性)</h3>
      <p>–Cloud consumers can scale or release their cloud-based IT resources automatically or manually.<br>–To provide flexible levels of scalability to IT resources is the inherent, built-in feature of clouds<br> <center><br>    <img 
    src="https://pic.imgdb.cn/item/622ed1af5baa1a80abab6382.jpg">   </p>
</center>


        <h3 id="Increased-Availability-and-Reliability-提高的可用性和可靠性"   >
          <a href="#Increased-Availability-and-Reliability-提高的可用性和可靠性" class="heading-link"><i class="fas fa-link"></i></a><a href="#Increased-Availability-and-Reliability-提高的可用性和可靠性" class="headerlink" title="Increased Availability and Reliability(提高的可用性和可靠性)"></a>Increased Availability and Reliability(提高的可用性和可靠性)</h3>
      <p>–An IT resource with increased availability is accessible for longer periods of time (for example, 22 hours out of a 24 hour day). Cloud providers generally offer “resilient” IT resources for which they are able to guarantee high levels of availability.<br>–An IT resource with increased reliability is able to better avoid and recover from exception conditions. The modular architecture of cloud environments provides extensive failover support that increases reliability  </p>

        <h2 id="Risks-and-Challenges风险与挑战"   >
          <a href="#Risks-and-Challenges风险与挑战" class="heading-link"><i class="fas fa-link"></i></a><a href="#Risks-and-Challenges风险与挑战" class="headerlink" title="Risks and Challenges风险与挑战"></a>Risks and Challenges风险与挑战</h2>
      <p>–Increased Security Vulnerabilities<br>        增加的安全漏洞</p>
 <center>
    <img src="https://pic.imgdb.cn/item/622ed22e5baa1a80abab99ef.jpg">
   </center>

<p>–Reduced Operational Governance Control<br>       降低的运营管理控制</p>
 <center>
    <img src="https://pic.imgdb.cn/item/622ed25d5baa1a80ababaa86.jpg">
</center>

<p>–Limited Portability Between Cloud Providers<br>云提供者之间有限的可移植性  </p>

        <h2 id="summary"   >
          <a href="#summary" class="heading-link"><i class="fas fa-link"></i></a><a href="#summary" class="headerlink" title="summary"></a>summary</h2>
      <p>–cloud computing  云计算<br> –cloud 云<br> –IT resource IT资源<br> –on-premise  企业内部的<br> –cloud consumer 云用户<br> –cloud provider  云提供者<br>– horizontal scaling  水平扩展<br> –vertical scaling  垂直扩展<br> –cloud service  云服务<br>– cloud service consumer  云服务用户  </p>
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</div><footer class="post-footer"><div class="post-ending ending"><div class="ending__text">------ 本文结束，感谢您的阅读 ------</div></div><div class="post-copyright copyright"><div class="copyright-author"><span class="copyright-author__name">本文作者: </span><span class="copyright-author__value"><a href="https://kohler19.gitee.io">李恺龙</a></span></div><div class="copyright-link"><span class="copyright-link__name">本文链接: </span><span class="copyright-link__value"><a href="https://kohler19.gitee.io/2022/03/14/cloud-computing1/">https://kohler19.gitee.io/2022/03/14/cloud-computing1/</a></span></div><div class="copyright-notice"><span class="copyright-notice__name">版权声明: </span><span class="copyright-notice__value">本博客所有文章除特别声明外，均采用 <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/deed.en" rel="external nofollow" target="_blank">BY-NC-SA</a> 许可协议。转载请注明出处！</span></div></div><div class="post-tags"><span class="post-tags-item"><span class="post-tags-item__icon"><i class="fas fa-tag"></i></span><a class="post-tags-item__link" href="https://kohler19.gitee.io/tags/%E4%BA%91%E8%AE%A1%E7%AE%97/">云计算</a></span><span class="post-tags-item"><span class="post-tags-item__icon"><i class="fas fa-tag"></i></span><a class="post-tags-item__link" href="https://kohler19.gitee.io/tags/cloud-computing/">cloud-computing</a></span></div><nav class="post-paginator paginator"><div class="paginator-prev"><a class="paginator-prev__link" href="/2022/03/15/Software-engineering-economics1/"><span class="paginator-prev__icon"><i class="fas fa-angle-left"></i></span><span class="paginator-prev__text">软件工程经济学第一章</span></a></div><div class="paginator-next"><a class="paginator-next__link" href="/2022/03/13/New-standard-Japanese-Volume-I/"><span class="paginator-prev__text">新标日语上册</span><span class="paginator-next__icon"><i class="fas fa-angle-right"></i></span></a></div></nav></footer></div></div><div class="comments" id="comments"><div id="valine-container"></div></div></div><div class="sidebar-wrap" id="sidebar-wrap"><aside class="sidebar" id="sidebar"><div class="sidebar-nav"><span class="sidebar-nav-toc current">文章目录</span><span class="sidebar-nav-ov">站点概览</span></div><section class="sidebar-toc"><ol class="toc"><li class="toc-item toc-level-1"><a class="toc-link" href="#Cloud-Computing-Chapter3"><span class="toc-number">1.</span> <span class="toc-text">
          Cloud Computing Chapter3</span></a><ol class="toc-child"><li class="toc-item toc-level-2"><a class="toc-link" href="#origins-and-Influences%EF%BC%88%E8%B5%B7%E6%BA%90%E5%92%8C%E5%BD%B1%E5%93%8D%EF%BC%89"><span class="toc-number">1.1.</span> <span class="toc-text">
          origins and Influences（起源和影响）</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#Definitions"><span class="toc-number">1.1.1.</span> <span class="toc-text">
          Definitions</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#Business-Drivers-%E5%95%86%E4%B8%9A%E9%A9%B1%E5%8A%A8%E5%8A%9B"><span class="toc-number">1.1.2.</span> <span class="toc-text">
          Business Drivers 商业驱动力</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#Technology-Innovations-%E6%8A%80%E6%9C%AF%E5%88%9B%E6%96%B0"><span class="toc-number">1.1.3.</span> <span class="toc-text">
          Technology Innovations 技术创新</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#Basic-Concepts-and-Terminology"><span class="toc-number">1.2.</span> <span class="toc-text">
          Basic Concepts and Terminology</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#Cloud"><span class="toc-number">1.2.1.</span> <span class="toc-text">
          Cloud</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#IT-Resource"><span class="toc-number">1.2.2.</span> <span class="toc-text">
          IT Resource</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#On-Premise-%E4%BC%81%E4%B8%9A%E5%86%85%E9%83%A8%E7%9A%84"><span class="toc-number">1.2.3.</span> <span class="toc-text">
          On-Premise  企业内部的</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#Cloud-Consumers-and-Cloud-Providers"><span class="toc-number">1.2.4.</span> <span class="toc-text">
          Cloud Consumers and Cloud Providers</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#Scaling-%E5%8F%AF%E6%89%A9%E5%B1%95%E6%80%A7"><span class="toc-number">1.2.5.</span> <span class="toc-text">
          Scaling 可扩展性</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#Cloud-Service-%E4%BA%91%E6%9C%8D%E5%8A%A1"><span class="toc-number">1.2.6.</span> <span class="toc-text">
          Cloud Service 云服务</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#Cloud-Service-Consumer-%E4%BA%91%E6%9C%8D%E5%8A%A1%E7%94%A8%E6%88%B7"><span class="toc-number">1.2.7.</span> <span class="toc-text">
          Cloud Service Consumer  云服务用户</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#Goals-and-Benefits-%E7%9B%AE%E6%A0%87%E5%92%8C%E6%94%B6%E7%9B%8A"><span class="toc-number">1.3.</span> <span class="toc-text">
          Goals and Benefits  目标和收益</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#Reduced-Investments-and-Proportional-Costs-%E9%99%8D%E4%BD%8E%E7%9A%84%E6%8A%95%E8%B5%84%E4%B8%8E%E6%88%90%E6%AF%94%E4%BE%8B%E7%9A%84%E5%BC%80%E9%94%80"><span class="toc-number">1.3.1.</span> <span class="toc-text">
          Reduced Investments and Proportional Costs(降低的投资与成比例的开销)</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#Increased-Scalability-%E6%8F%90%E9%AB%98%E7%9A%84%E5%8F%AF%E6%89%A9%E5%B1%95%E6%80%A7"><span class="toc-number">1.3.2.</span> <span class="toc-text">
          Increased Scalability (提高的可扩展性)</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#Increased-Availability-and-Reliability-%E6%8F%90%E9%AB%98%E7%9A%84%E5%8F%AF%E7%94%A8%E6%80%A7%E5%92%8C%E5%8F%AF%E9%9D%A0%E6%80%A7"><span class="toc-number">1.3.3.</span> <span class="toc-text">
          Increased Availability and Reliability(提高的可用性和可靠性)</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#Risks-and-Challenges%E9%A3%8E%E9%99%A9%E4%B8%8E%E6%8C%91%E6%88%98"><span class="toc-number">1.4.</span> <span class="toc-text">
          Risks and Challenges风险与挑战</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#summary"><span class="toc-number">1.5.</span> <span class="toc-text">
          summary</span></a></li></ol></li></ol></section><!-- ov = overview--><section class="sidebar-ov hide"><div class="sidebar-ov-author"><div class="sidebar-ov-author__avatar"><img class="sidebar-ov-author__avatar_img" src="https://s4.ax1x.com/2022/01/03/Tb2VW6.png" alt="avatar"></div><p class="sidebar-ov-author__text">格物致知，知行合一</p></div><div class="sidebar-ov-social"><a class="sidebar-ov-social-item" href="https://s4.ax1x.com/2022/01/03/Tb8ZB4.png" target="_blank" rel="noopener" data-popover="微信" data-popover-pos="up"><span class="sidebar-ov-social-item__icon"><i class="fab fa-weixin"></i></span></a><a class="sidebar-ov-social-item" href="mailto:lklong@88.com" target="_blank" rel="noopener" data-popover="social.Email" data-popover-pos="up"><span class="sidebar-ov-social-item__icon">lklong@88.com</span></a></div><div class="sidebar-ov-cc"><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/deed.en" target="_blank" rel="noopener" data-popover="知识共享许可协议" data-popover-pos="up"><img src="/images/cc-by-nc-sa.svg"></a></div></section><div class="sidebar-reading"><div class="sidebar-reading-info"><span class="sidebar-reading-info__text">你已阅读了 </span><span class="sidebar-reading-info__num">0</span><span class="sidebar-reading-info__perc">%</span></div><div class="sidebar-reading-line"></div></div></aside></div><div class="clearfix"></div></div></main><footer class="footer" id="footer"><div class="footer-inner"><div><span>Copyright © 2023</span><span class="footer__icon"><i class="fas fa-heart"></i></span><span>愷龍 All Rights Reserved</span></div><div><span>由 <a href="http://hexo.io/" title="Hexo" target="_blank" rel="noopener">Hexo</a> 强力驱动</span><span> v5.4.0</span><span class="footer__devider">|</span><span>主题 - <a href="https://github.com/liuyib/hexo-theme-stun/" title="Stun" target="_blank" rel="noopener">Stun</a></span><span> v2.6.2</span></div></div></footer><div class="loading-bar" id="loading-bar"><div class="loading-bar__progress"></div></div><div class="back2top" id="back2top"><span class="back2top__icon"><i class="fas fa-rocket"></i></span></div></div><div class="search-mask"></div><div class="search-popup"><span class="search-close"></span><div class="search-input"><input placeholder="搜索文章（支持多关键词，请用空格分隔）"></div><div class="search-results"></div></div><script src="https://cdn.jsdelivr.net/npm/jquery@v3.4.1/dist/jquery.min.js"></script><script src="https://cdn.jsdelivr.net/npm/velocity-animate@1.5.2/velocity.min.js"></script><script src="https://cdn.jsdelivr.net/npm/velocity-animate@1.5.2/velocity.ui.min.js"></script><script>function initSearch() {
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